From dc284987fa4621be63c8644fca1ad04edf5a1e76 Mon Sep 17 00:00:00 2001
From: Sergei Trofimovich <slyich@gmail.com>
Date: Sat, 29 Mar 2025 22:49:37 +0000
Subject: [PATCH] configure.ac: use 64-bit file API on 32-bit linux

Without the change `graphviz` fails to run when built against
`i686-linux` target and installed on thew filesystem with 64-bit
inodes (`btrfs` with many files in my case):

    $ dot a.dot -T png > a.png
    Format: "png" not recognized. No formats found.
    Perhaps "dot -c" needs to be run (with installer's privileges) to register the plugins?

With the change it runs as expected:

    $ dot a.dot -T png > a.png

This happens because 32-bit file APIs skip or error out files that
require 64-bit values in inode numbers, sizes or similar places defined
by `off_t` type.

The change enables the respective macros to enable 64-bit API.
---
 configure.ac | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/configure.ac b/configure.ac
index a5689c3944..9ded86e6c7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -291,6 +291,9 @@ AC_PROG_OBJC
 dnl ===========================================================================
 dnl Set GCC compiler flags
 
+# Use 64-bit off_t on 32-bit Linux
+AC_SYS_LARGEFILE
+
 if [ test "${GCC}" = "yes" ]
 then
   # Enable common warnings flags
-- 
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